Haunted House 2019: Alien Infestation

I help run the haunted house at my kids' grade school. Our theme was Alien Infestation. We wanted to use the school as the school, barricading the kindergarten hallway to look like humanity's last stand against an alien attack: think 28 Days Later or Children Of Men. This quick concept was to help drum up other parents to help build it. Of coarse the final installation was less scary. We only want to slightly terrify the 5 year olds...